Our first steps tour and our frequently asked questions will help you a lot after registration. They explain how to customize the interface (for example the language), how to upload files and our basic licensing policy (Wikimedia Commons only accepts free content). You don't need technical skills in order to contribute here. Be bold contributing here and assume good faith for the intentions of others. This is a wiki—it is really easy.

When picking categories, try to choose a specific category ("Astronomical diagrams") over a generic one ("Illustrations"). Pro-tip: The CommonSense tool can help you find the best category for your image.

Thanks again for your uploads! More information about categorization can be found in Commons:Categories, and don't hesitate to leave a note on the help desk.

There seems to be a problem regarding the description and/or licensing of this particular file. It has been found that you've added in the image's description only a Template that's not a license and although it provides useful information about the image, it's not a valid license. Could you please resolve this problem, adding the license in the image linked above? You can edit the description page and change the text. Uploading a new version of the file does not change the description of the file. This page may give you more hints on which license to choose. Thank you.

This message was added automatically by Nikbot, if you need some help about it please read the text above again and follow the links in it, if you still need help ask at the →Commons:Help desk in any language you like to use. --Nikbot 10:25, 1 February 2012 (UTC)